Objectives: This study aimed to investigate the possible association between vitamin D and adiponectin, a biomarker of insulin resistance, in pre- and early postmenopausal women with obesity. Methods: This cross-sectional study included 118 obese women aged 45–55 years (60 premenopausal and 58 postmenopausal women). Anthropometric measurements were obtained. Body fat percentage and visceral fat were assessed using bioelectrical impedance analysis. Serum adiponectin and 25-hydroxyvitamin D (25(OH)D) levels were analyzed using chemiluminescent microparticle immunoassay. Results: Serum adiponectin levels were higher in the postmenopausal group (7.7 ± 3.8 µg/mL) than in the premenopausal group (5.6 ± 3.8 µg/mL) (P = 0.003). Serum 25(OH)D levels were lower in the postmenopausal group (15.4 ± 6.4 ng/mL) than in the premenopausal group (20.2 ± 4.7 ng/mL) (P < 0.001). There was no significant correlation between serum adiponectin and 25(OH)D in either group (r = −0.008, P = 0.949 in the premenopausal group; r = −0.135, P = 0.312 in the postmenopausal group). Multiple linear regression analysis showed that, after controlling for age, waist circumference, and serum vitamin D levels, adiponectin levels increased by an average of 0.208 units for each 1-cm increase in hip circumference. Conclusions Serum vitamin D levels were not correlated with adiponectin levels in obese pre- and early postmenopausal women.Further studies are needed to investigate factors influencing adiponectin and determine whether vitamin D supplementation provides benefits for obese middle-aged women.